New FWPA-supported research will benefit the conservation of Tasmania’s threatened giant freshwater crayfish (Astacopsis gouldi) during forestry operations. Threats to the species include habitat loss, disturbance or sedimentation of waterways and climate change.
Forestry operations including harvesting, roading and plantation establishment all have the potential to create adverse impacts on crayfish populations through the loss of riparian canopy cover, increased runoff, sedimentation, changes in hydrology and chemical spraying.
Jodie Mason, FWPA’s Head of Forest Research, said while the giant freshwater crayfish is the world’s largest freshwater invertebrate, it is also elusive, favouring shaded waterway habitats with undercut banks, making detection a time consuming and difficult process.
“A rapid, sensitive and cost-effective method was therefore needed to enable easier detection of giant freshwater crayfish from water samples, and allowing for a safer and more efficient monitoring approach,” Mason said.
Using tissue samples from giant freshwater crayfish the research team were able to design a genetic assay specific to the species by using environmental DNA (eDNA) to detect the crayfish in water samples.
Essentially, eDNA allows samples of water, sediment, ice or air to be collected from the environment and analysed for genetic material to detect the presence or absence of a species.
The assay was tested for efficacy in a laboratory setting, followed by successful testing in freshwater streams where the giant freshwater crayfish is known to occur.
The research team behind this groundbreaking project includes Amelia Koch from the Tasmanian Forest Practices Authority, Associate Professor Leon Barmuta from the University of Tasmania, and Alejandro Trujillo Gonzalez from the University of Canberra.
“This technique can facilitate the development of a population monitoring program, be used to conduct research on habitat associations of the species or the effectiveness of management actions, or to update management tools such as the habitat availability map used by the Tasmanian forest industry.” said researcher Amelia Koch from Forest Practices Authority.
The research is part of a larger project aimed at enhancing biodiversity conservation and sustainable forestry practices in Tasmania, and includes research on Wedge-tailed eagles, Masked owls, Grey goshawks, Tamanian devils and quolls.
This comprehensive project (Project number: VNC457-1718 Sub-report 3), funded by FWPA through funds from Tasmanian forest managers, the Forest Practices Authority and the Australian Government, focuses on integrating innovative scientific techniques, such as eDNA analysis, to improve monitoring and management strategies for threatened species.
Discover more about this work by listening to our 2022 WoodChat episode on the project.
